Rajoy: Catalan referendum is threat to ‘constitutional order’

Opening negotiations over an independence vote in Catalonia would go against Spain's "constitutional order," Spanish Prime Minister Mariano Rajoy wrote Thursday in a letter to Catalonia's regional President Carles Puigdemont, who formally asked to start negotiations over a referendum one day earlier.

Rajoy's letter is the latest symptom of growing tensions between Madrid and the pro-independence Catalan government over its demand for an independence vote, which Rajoy labeled “political, juridical and social nonsense” on Monday.

The Catalan government promised a vote in the fall but Madrid has vowed to prevent it by any means necessary.

"I consider it inexcusable to have to reiterate to you not only the impossibility of taking part in what you propose but also the impossibility for your Government to raise such a grave threat to coexistence and constitutional order," Rajoy wrote.

The Catalan government has drafted a secret plan to move toward independence even if the Spanish government forbids it from holding a referendum, El Pais reported Monday.